300 lines
7.8 KiB
C
300 lines
7.8 KiB
C
|
/*
|
||
|
* misc.c
|
||
|
*
|
||
|
* PURPOSE
|
||
|
* Miscellaneous routines for the OSTA-UDF(tm) filesystem.
|
||
|
*
|
||
|
* COPYRIGHT
|
||
|
* This file is distributed under the terms of the GNU General Public
|
||
|
* License (GPL). Copies of the GPL can be obtained from:
|
||
|
* ftp://prep.ai.mit.edu/pub/gnu/GPL
|
||
|
* Each contributing author retains all rights to their own work.
|
||
|
*
|
||
|
* (C) 1998 Dave Boynton
|
||
|
* (C) 1998-2004 Ben Fennema
|
||
|
* (C) 1999-2000 Stelias Computing Inc
|
||
|
*
|
||
|
* HISTORY
|
||
|
*
|
||
|
* 04/19/99 blf partial support for reading/writing specific EA's
|
||
|
*/
|
||
|
|
||
|
#include "udfdecl.h"
|
||
|
|
||
|
#include <linux/fs.h>
|
||
|
#include <linux/string.h>
|
||
|
#include <linux/buffer_head.h>
|
||
|
#include <linux/crc-itu-t.h>
|
||
|
|
||
|
#include "udf_i.h"
|
||
|
#include "udf_sb.h"
|
||
|
|
||
|
struct buffer_head *udf_tgetblk(struct super_block *sb, int block)
|
||
|
{
|
||
|
if (UDF_QUERY_FLAG(sb, UDF_FLAG_VARCONV))
|
||
|
return sb_getblk(sb, udf_fixed_to_variable(block));
|
||
|
else
|
||
|
return sb_getblk(sb, block);
|
||
|
}
|
||
|
|
||
|
struct buffer_head *udf_tread(struct super_block *sb, int block)
|
||
|
{
|
||
|
if (UDF_QUERY_FLAG(sb, UDF_FLAG_VARCONV))
|
||
|
return sb_bread(sb, udf_fixed_to_variable(block));
|
||
|
else
|
||
|
return sb_bread(sb, block);
|
||
|
}
|
||
|
|
||
|
struct genericFormat *udf_add_extendedattr(struct inode *inode, uint32_t size,
|
||
|
uint32_t type, uint8_t loc)
|
||
|
{
|
||
|
uint8_t *ea = NULL, *ad = NULL;
|
||
|
int offset;
|
||
|
uint16_t crclen;
|
||
|
struct udf_inode_info *iinfo = UDF_I(inode);
|
||
|
|
||
|
ea = iinfo->i_ext.i_data;
|
||
|
if (iinfo->i_lenEAttr) {
|
||
|
ad = iinfo->i_ext.i_data + iinfo->i_lenEAttr;
|
||
|
} else {
|
||
|
ad = ea;
|
||
|
size += sizeof(struct extendedAttrHeaderDesc);
|
||
|
}
|
||
|
|
||
|
offset = inode->i_sb->s_blocksize - udf_file_entry_alloc_offset(inode) -
|
||
|
iinfo->i_lenAlloc;
|
||
|
|
||
|
/* TODO - Check for FreeEASpace */
|
||
|
|
||
|
if (loc & 0x01 && offset >= size) {
|
||
|
struct extendedAttrHeaderDesc *eahd;
|
||
|
eahd = (struct extendedAttrHeaderDesc *)ea;
|
||
|
|
||
|
if (iinfo->i_lenAlloc)
|
||
|
memmove(&ad[size], ad, iinfo->i_lenAlloc);
|
||
|
|
||
|
if (iinfo->i_lenEAttr) {
|
||
|
/* check checksum/crc */
|
||
|
if (eahd->descTag.tagIdent !=
|
||
|
cpu_to_le16(TAG_IDENT_EAHD) ||
|
||
|
le32_to_cpu(eahd->descTag.tagLocation) !=
|
||
|
iinfo->i_location.logicalBlockNum)
|
||
|
return NULL;
|
||
|
} else {
|
||
|
struct udf_sb_info *sbi = UDF_SB(inode->i_sb);
|
||
|
|
||
|
size -= sizeof(struct extendedAttrHeaderDesc);
|
||
|
iinfo->i_lenEAttr +=
|
||
|
sizeof(struct extendedAttrHeaderDesc);
|
||
|
eahd->descTag.tagIdent = cpu_to_le16(TAG_IDENT_EAHD);
|
||
|
if (sbi->s_udfrev >= 0x0200)
|
||
|
eahd->descTag.descVersion = cpu_to_le16(3);
|
||
|
else
|
||
|
eahd->descTag.descVersion = cpu_to_le16(2);
|
||
|
eahd->descTag.tagSerialNum =
|
||
|
cpu_to_le16(sbi->s_serial_number);
|
||
|
eahd->descTag.tagLocation = cpu_to_le32(
|
||
|
iinfo->i_location.logicalBlockNum);
|
||
|
eahd->impAttrLocation = cpu_to_le32(0xFFFFFFFF);
|
||
|
eahd->appAttrLocation = cpu_to_le32(0xFFFFFFFF);
|
||
|
}
|
||
|
|
||
|
offset = iinfo->i_lenEAttr;
|
||
|
if (type < 2048) {
|
||
|
if (le32_to_cpu(eahd->appAttrLocation) <
|
||
|
iinfo->i_lenEAttr) {
|
||
|
uint32_t aal =
|
||
|
le32_to_cpu(eahd->appAttrLocation);
|
||
|
memmove(&ea[offset - aal + size],
|
||
|
&ea[aal], offset - aal);
|
||
|
offset -= aal;
|
||
|
eahd->appAttrLocation =
|
||
|
cpu_to_le32(aal + size);
|
||
|
}
|
||
|
if (le32_to_cpu(eahd->impAttrLocation) <
|
||
|
iinfo->i_lenEAttr) {
|
||
|
uint32_t ial =
|
||
|
le32_to_cpu(eahd->impAttrLocation);
|
||
|
memmove(&ea[offset - ial + size],
|
||
|
&ea[ial], offset - ial);
|
||
|
offset -= ial;
|
||
|
eahd->impAttrLocation =
|
||
|
cpu_to_le32(ial + size);
|
||
|
}
|
||
|
} else if (type < 65536) {
|
||
|
if (le32_to_cpu(eahd->appAttrLocation) <
|
||
|
iinfo->i_lenEAttr) {
|
||
|
uint32_t aal =
|
||
|
le32_to_cpu(eahd->appAttrLocation);
|
||
|
memmove(&ea[offset - aal + size],
|
||
|
&ea[aal], offset - aal);
|
||
|
offset -= aal;
|
||
|
eahd->appAttrLocation =
|
||
|
cpu_to_le32(aal + size);
|
||
|
}
|
||
|
}
|
||
|
/* rewrite CRC + checksum of eahd */
|
||
|
crclen = sizeof(struct extendedAttrHeaderDesc) - sizeof(struct tag);
|
||
|
eahd->descTag.descCRCLength = cpu_to_le16(crclen);
|
||
|
eahd->descTag.descCRC = cpu_to_le16(crc_itu_t(0, (char *)eahd +
|
||
|
sizeof(struct tag), crclen));
|
||
|
eahd->descTag.tagChecksum = udf_tag_checksum(&eahd->descTag);
|
||
|
iinfo->i_lenEAttr += size;
|
||
|
return (struct genericFormat *)&ea[offset];
|
||
|
}
|
||
|
if (loc & 0x02)
|
||
|
;
|
||
|
|
||
|
return NULL;
|
||
|
}
|
||
|
|
||
|
struct genericFormat *udf_get_extendedattr(struct inode *inode, uint32_t type,
|
||
|
uint8_t subtype)
|
||
|
{
|
||
|
struct genericFormat *gaf;
|
||
|
uint8_t *ea = NULL;
|
||
|
uint32_t offset;
|
||
|
struct udf_inode_info *iinfo = UDF_I(inode);
|
||
|
|
||
|
ea = iinfo->i_ext.i_data;
|
||
|
|
||
|
if (iinfo->i_lenEAttr) {
|
||
|
struct extendedAttrHeaderDesc *eahd;
|
||
|
eahd = (struct extendedAttrHeaderDesc *)ea;
|
||
|
|
||
|
/* check checksum/crc */
|
||
|
if (eahd->descTag.tagIdent !=
|
||
|
cpu_to_le16(TAG_IDENT_EAHD) ||
|
||
|
le32_to_cpu(eahd->descTag.tagLocation) !=
|
||
|
iinfo->i_location.logicalBlockNum)
|
||
|
return NULL;
|
||
|
|
||
|
if (type < 2048)
|
||
|
offset = sizeof(struct extendedAttrHeaderDesc);
|
||
|
else if (type < 65536)
|
||
|
offset = le32_to_cpu(eahd->impAttrLocation);
|
||
|
else
|
||
|
offset = le32_to_cpu(eahd->appAttrLocation);
|
||
|
|
||
|
while (offset < iinfo->i_lenEAttr) {
|
||
|
gaf = (struct genericFormat *)&ea[offset];
|
||
|
if (le32_to_cpu(gaf->attrType) == type &&
|
||
|
gaf->attrSubtype == subtype)
|
||
|
return gaf;
|
||
|
else
|
||
|
offset += le32_to_cpu(gaf->attrLength);
|
||
|
}
|
||
|
}
|
||
|
|
||
|
return NULL;
|
||
|
}
|
||
|
|
||
|
/*
|
||
|
* udf_read_tagged
|
||
|
*
|
||
|
* PURPOSE
|
||
|
* Read the first block of a tagged descriptor.
|
||
|
*
|
||
|
* HISTORY
|
||
|
* July 1, 1997 - Andrew E. Mileski
|
||
|
* Written, tested, and released.
|
||
|
*/
|
||
|
struct buffer_head *udf_read_tagged(struct super_block *sb, uint32_t block,
|
||
|
uint32_t location, uint16_t *ident)
|
||
|
{
|
||
|
struct tag *tag_p;
|
||
|
struct buffer_head *bh = NULL;
|
||
|
u8 checksum;
|
||
|
|
||
|
/* Read the block */
|
||
|
if (block == 0xFFFFFFFF)
|
||
|
return NULL;
|
||
|
|
||
|
bh = udf_tread(sb, block);
|
||
|
if (!bh) {
|
||
|
udf_err(sb, "read failed, block=%u, location=%d\n",
|
||
|
block, location);
|
||
|
return NULL;
|
||
|
}
|
||
|
|
||
|
tag_p = (struct tag *)(bh->b_data);
|
||
|
|
||
|
*ident = le16_to_cpu(tag_p->tagIdent);
|
||
|
|
||
|
if (location != le32_to_cpu(tag_p->tagLocation)) {
|
||
|
udf_debug("location mismatch block %u, tag %u != %u\n",
|
||
|
block, le32_to_cpu(tag_p->tagLocation), location);
|
||
|
goto error_out;
|
||
|
}
|
||
|
|
||
|
/* Verify the tag checksum */
|
||
|
checksum = udf_tag_checksum(tag_p);
|
||
|
if (checksum != tag_p->tagChecksum) {
|
||
|
udf_err(sb, "tag checksum failed, block %u: 0x%02x != 0x%02x\n",
|
||
|
block, checksum, tag_p->tagChecksum);
|
||
|
goto error_out;
|
||
|
}
|
||
|
|
||
|
/* Verify the tag version */
|
||
|
if (tag_p->descVersion != cpu_to_le16(0x0002U) &&
|
||
|
tag_p->descVersion != cpu_to_le16(0x0003U)) {
|
||
|
udf_err(sb, "tag version 0x%04x != 0x0002 || 0x0003, block %u\n",
|
||
|
le16_to_cpu(tag_p->descVersion), block);
|
||
|
goto error_out;
|
||
|
}
|
||
|
|
||
|
/* Verify the descriptor CRC */
|
||
|
if (le16_to_cpu(tag_p->descCRCLength) + sizeof(struct tag) > sb->s_blocksize ||
|
||
|
le16_to_cpu(tag_p->descCRC) == crc_itu_t(0,
|
||
|
bh->b_data + sizeof(struct tag),
|
||
|
le16_to_cpu(tag_p->descCRCLength)))
|
||
|
return bh;
|
||
|
|
||
|
udf_debug("Crc failure block %d: crc = %d, crclen = %d\n", block,
|
||
|
le16_to_cpu(tag_p->descCRC),
|
||
|
le16_to_cpu(tag_p->descCRCLength));
|
||
|
error_out:
|
||
|
brelse(bh);
|
||
|
return NULL;
|
||
|
}
|
||
|
|
||
|
struct buffer_head *udf_read_ptagged(struct super_block *sb,
|
||
|
struct kernel_lb_addr *loc,
|
||
|
uint32_t offset, uint16_t *ident)
|
||
|
{
|
||
|
return udf_read_tagged(sb, udf_get_lb_pblock(sb, loc, offset),
|
||
|
loc->logicalBlockNum + offset, ident);
|
||
|
}
|
||
|
|
||
|
void udf_update_tag(char *data, int length)
|
||
|
{
|
||
|
struct tag *tptr = (struct tag *)data;
|
||
|
length -= sizeof(struct tag);
|
||
|
|
||
|
tptr->descCRCLength = cpu_to_le16(length);
|
||
|
tptr->descCRC = cpu_to_le16(crc_itu_t(0, data + sizeof(struct tag), length));
|
||
|
tptr->tagChecksum = udf_tag_checksum(tptr);
|
||
|
}
|
||
|
|
||
|
void udf_new_tag(char *data, uint16_t ident, uint16_t version, uint16_t snum,
|
||
|
uint32_t loc, int length)
|
||
|
{
|
||
|
struct tag *tptr = (struct tag *)data;
|
||
|
tptr->tagIdent = cpu_to_le16(ident);
|
||
|
tptr->descVersion = cpu_to_le16(version);
|
||
|
tptr->tagSerialNum = cpu_to_le16(snum);
|
||
|
tptr->tagLocation = cpu_to_le32(loc);
|
||
|
udf_update_tag(data, length);
|
||
|
}
|
||
|
|
||
|
u8 udf_tag_checksum(const struct tag *t)
|
||
|
{
|
||
|
u8 *data = (u8 *)t;
|
||
|
u8 checksum = 0;
|
||
|
int i;
|
||
|
for (i = 0; i < sizeof(struct tag); ++i)
|
||
|
if (i != 4) /* position of checksum */
|
||
|
checksum += data[i];
|
||
|
return checksum;
|
||
|
}
|